President Michel Temer is accused of taking bribes in return for helping shape a decree regulating Brazil's ports.

Lawyers for Brazil's President Michel Temer have asked the country's top court to annul a federal police report that recommended he and his close associates be charged with corruption and their assets confiscated.

Police have been investigating Temer for allegedly taking bribes in return for helping shape a decree regulating Brazil's ports, and in particular for extending concessions in the port of Santos to benefit companies owned by close associates.

Temer maintains his innocence. He has faced several corruption allegations but is immune from prosecution while in office, unless the Supreme Court decides to strip his immunity.

The president's defence team argued that the federal police should not be able to charge Temer without the authorization of the Supreme Court or the public prosecutor's office.

Temer's term - during which he has become one of the most unpopular Brazilian presidents in decades - ends on January 1, and with it his immunity from prosecution.

Congress voted twice last year to block Temer from standing trial in the Supreme Court on three corruption charges levelled against him.

The federal police report recommended that Temer, his daughter Maristela, former adviser Rodrigo Rocha Loures and eight others face charges and have their assets confiscated for their role in allegedly laundering bribes through real estate transactions.

Carlos Marun, Brazil's minister of government, said on Wednesday that Temer, who took office in 2016 after former President Dilma Rousseff was impeached, was "outraged and shaken" by the police report.

Supreme Court Justice Luis Roberto Barroso, who is overseeing the case, said on Tuesday he would wait to see the findings of Brazil's public prosecutor’s office before deciding on how to proceed.

The allegations come amid a polarising presidential election season in Brazil.

Far-right presidential candidate Jair Bolsonaro, who was stabbed at a campaign rally in September, got the most votes in the first-round polls that were held on October 8, with 46 percent of the vote, coming close to an outright majority that would have pre-empted a second-round contest.

Fernando Haddad of the Workers' Party is Bolsonaro's challenger, but public opinion polls show him trailing the frontrunner.

Second-round voting to determine Brazil's next president will take place on October 28.